Let _a_, _b_, _c_, _d_, _e_, _f_, _g_, _h_ be the Earth in eight
different parts of it’s Orbit, equidistant from one another; _Ns_ it’s
Axis, _N_ the north Pole, _s_ the south Pole, and _S_ the Sun nearly in
the center of the Earth’s Orbit § 18. As the Earth goes round the Sun
according to the order of the letters _abcd_, &c. it’s Axis _Ns_ keeps
the same obliquity, and is still parallel to the line _MNs_. When the
Earth is at _a_, it’s north Pole inclines toward the Sun, and brings all
the northern places more into the light than at any other time of the
year. But when the Earth is at _e_ in the opposite time of the year, the
north Pole declines from the Sun, which occasions the northern places to
be more in the dark than in the light; and the reverse at the southern
places, as is evident by the Figure, which I have taken from Dr. LONG’s
Astronomy. When the Earth is either at _c_ or _g_, it’s Axis inclines
not either to or from the Sun, but lies sidewise to him; and then the
Poles are in the boundary of light and darkness; and the Sun, being
directly over the Equator, makes equal day and night at all places. When
the Earth is at _b_ it is half way between the Summer Solstice and
Harvest Equinox; when it is at _d_ it is half way from the Harvest
Equinox to the Winter Solstice; at _f_ half way from the Winter Solstice
to the Spring Equinox: and at _h_ half way from the Spring Equinox to
the Summer Solstice.
[Sidenote: Fig. II.